Search Publications

Radial velocity confirmation of K2-100b: a young, highly irradiated, and low-density transiting hot Neptune
DOI: 10.1093/mnras/stz2569 Bibcode: 2019MNRAS.490..698B

Tamura, M.; Aigrain, S.; Pagano, I. +37 more

We present a detailed analysis of HARPS-N radial velocity observations of K2-100, a young and active star in the Praesepe cluster, which hosts a transiting planet with a period of 1.7 d. We model the activity-induced radial velocity variations of the host star with a multidimensional Gaussian Process framework and detect a planetary signal of 10.6…

2019 Monthly Notices of the Royal Astronomical Society
Gaia 63
Characterization of the L 98-59 multi-planetary system with HARPS. Mass characterization of a hot super-Earth, a sub-Neptune, and a mass upper limit on the third planet
DOI: 10.1051/0004-6361/201935957 Bibcode: 2019A&A...629A.111C

Bouchy, F.; Doyon, R.; Ségransan, D. +33 more


Aims: L 98-59 (TIC 307210830, TOI-175) is a nearby M3 dwarf around which TESS revealed three small transiting planets (0.80, 1.35, 1.57 Earth radii) in a compact configuration with orbital periods shorter than 7.5 days. Here we aim to measure the masses of the known transiting planets in this system using precise radial velocity (RV) measurem…

2019 Astronomy and Astrophysics
Gaia 63
Hard X-ray view on intermediate polars in the Gaia era
DOI: 10.1093/mnras/sty2952 Bibcode: 2019MNRAS.482.3622S

Doroshenko, Victor; Suleimanov, Valery F.; Werner, Klaus

The hardness of the X-ray spectra of intermediate polars (IPs) is determined mainly by the white dwarf (WD) compactness (mass-radius ratio, M/R) and, thus, hard X-ray spectra can be used to constrain the WD mass. An accurate mass estimate requires the finite size of the WD magnetosphere Rm to be taken into the account. We suggested to d…

2019 Monthly Notices of the Royal Astronomical Society
Gaia 63
Pulsating in Unison at Optical and X-Ray Energies: Simultaneous High Time Resolution Observations of the Transitional Millisecond Pulsar PSR J1023+0038
DOI: 10.3847/1538-4357/ab2fdf Bibcode: 2019ApJ...882..104P

Campana, S.; Stella, L.; Sanna, A. +22 more

PSR J1023+0038 is the first millisecond pulsar discovered to pulsate in the visible band; such a detection took place when the pulsar was surrounded by an accretion disk and also showed X-ray pulsations. We report on the first high time resolution observational campaign of this transitional pulsar in the disk state, using simultaneous observations…

2019 The Astrophysical Journal
XMM-Newton 63
Reconciling mass estimates of ultradiffuse galaxies
DOI: 10.1093/mnras/sty2891 Bibcode: 2019MNRAS.484..245L

Laporte, Chervin F. P.; Navarro, Julio F.; Agnello, Adriano

The virial masses of ultradiffuse galaxies (UDGs) have been estimated using the kinematics and abundance of their globular cluster populations, leading to disparate results. Some studies conclude that UDGs reside in massive dark matter haloes while van Dokkum et al., controversially, argue for the existence of UDGs with no dark matter at all. Here…

2019 Monthly Notices of the Royal Astronomical Society
eHST 63
Prevalence of SED Turndown among Classical Be Stars: Are All Be Stars Close Binaries?
DOI: 10.3847/1538-4357/ab48e7 Bibcode: 2019ApJ...885..147K

Hallinan, G.; Klement, Robert; Carciofi, A. C. +16 more

Rapid rotation is a fundamental characteristic of classical Be stars and a crucial property allowing for the formation of their circumstellar disks. Past evolution in a mass and angular momentum transferring binary system offers a plausible solution to how Be stars attained their fast rotation. Although the subdwarf remnants of mass donors in such…

2019 The Astrophysical Journal
AKARI Gaia 63
The mass-to-light ratios and the star formation histories of disc galaxies
DOI: 10.1093/mnras/sty3223 Bibcode: 2019MNRAS.483.1496S

Lelli, Federico; Schombert, James; McGaugh, Stacy

We combine new data from the main sequence (M* versus SFR) of star-forming galaxies and galaxy colours (from GALEX to Spitzer) with a flexible stellar population scheme to deduce the mass-to-light ratio (Υ*) of star-forming galaxies from the SPARC and S4G samples. We find that the main sequence for galaxies, partic…

2019 Monthly Notices of the Royal Astronomical Society
eHST 63
Anisotropy of the Milky Way’s Stellar Halo Using K Giants from LAMOST and Gaia
DOI: 10.3847/1538-3881/aafd2e Bibcode: 2019AJ....157..104B

Bird, Sarah A.; Yang, Chengqun; Liu, Chao +3 more

The anisotropy parameter β characterizes the extent to which orbits in stellar systems are predominantly radial or tangential and is likely to constrain, for the stellar halo of the Milky Way, scenarios for its formation and evolution. We have measured β as a function of Galactocentric radius from 5 to 100 kpc for 7664 metal-poor ([Fe/H] < -1.3…

2019 The Astronomical Journal
Gaia 63
Major Mergers Are Not the Dominant Trigger for High-accretion AGNs at z ∼ 2
DOI: 10.3847/1538-4357/ab385b Bibcode: 2019ApJ...882..141M

Cohen, Seth; van der Wel, Arjen; Windhorst, Rogier A. +8 more

Research over the past decade has shown diminishing evidence for major galaxy mergers being a dominant mechanism for the growth of supermassive black holes (BHs) in galaxies and the triggering of optically or X-ray-selected active galactic nuclei (AGNs). For the first time we test whether such a connection exists at least in the most “plausible” p…

2019 The Astrophysical Journal
eHST 63
A Uniform Retrieval Analysis of Ultra-cool Dwarfs. III. Properties of Y Dwarfs
DOI: 10.3847/1538-4357/ab16db Bibcode: 2019ApJ...877...24Z

Line, Michael R.; Schneider, Adam C.; Patience, Jennifer +1 more

Ultra-cool brown dwarfs offer a unique window into understanding substellar atmospheric physics and chemistry. Their strong molecular absorption bands at infrared wavelengths, Jupiter-like radii, cool temperatures, and lack of complicating stellar irradiation make them ideal test beds for understanding Jovian-like atmospheres. Here, we report the …

2019 The Astrophysical Journal
eHST 63